It has been hitherto known that N-substituted 2-amino-4-(hydroxymethylphosphinyl)-2-butenoic acid derivative is a synthetic intermediate of L-AMPB having herbicidal activity (Japanese Patent Laid-Open No. 92897/1981 (Patent Document 1), J. Org. Chem., 56, 1783-1788 (1991) (Non Patent Document 1)).
Up to date, a method for synthesizing by condensing 2-oxo-4-(hydroxymethylphosphinyl)-2-butanoic acid and acetamide (Japanese Patent Laid-Open No. 226993/1987 (Patent Document 2)) and a method for synthesizing by condensing phosphinylacetaldehyde derivative and isocyanoacetate (Non Patent Document 1) have been reported as a method for producing N-substituted-2-amino-4-(hydroxymethylphosphinyl)-2-butenoic acid derivative.
Also, a method for synthesizing a phosphorylglycine derivative and a phosphinylacetaldehyde derivative by a reaction of Horner-Emmons type has been reported (Patent Document 3).
    [Patent Document 1] Japanese Patent Laid-Open No. 92897/1981    [Patent Document 2] Japanese Patent Laid-Open No. 226993/1987    [Patent Document 3] WO 2008/114808    [Non-Patent Document 1] J. Org. Chem., 56, 1783-1788 (1991)